1) Field of the Invention
The present invention relates to a door-opening/closing apparatus for a door of a vehicle.
2) Description of the Related Art
A conventional door-opening/closing apparatus includes a clutch that is placed between a door-opening/closing mechanism and a motor that drives the door-opening/closing mechanism. The clutch can arbitrarily select a completely connected state, an incompletely connected state and a completely separated state. According to the door-opening/closing apparatus, in the completely connected state, the clutch connects the motor and the door-opening/closing mechanism to transmit the rotation of the motor to the door-opening/closing mechanism, thereby opening and closing the door. In the completely separated state, the transmission of the rotation of the motor is cut off and the door can be manually opened and closed. In the incompletely connected state, the clutch is brought into a half clutch state to apply a braking force to the door, and the door can be closed by applying a force to the door. The conventional door-opening/closing apparatus has been disclosed in, for example, Japanese Patent Application Laid-open No. 2001-132327.
Although the door-opening/closing mechanism can be braked in the incompletely connected state and the door can be stopped in any position, since the braking force is obtained by bringing the clutch into the half clutch state, an electricity is always supplied to the clutch. For this reason, since the electricity must be supplied also when the door is braked at an arbitrary position, a battery may be exhausted in an extreme case.